| Abstract: | Two types of ethylene-vinylacetate copolymers, containing 16% and 9% of vinylacetate, respectively, were crosslinked with dicumyl peroxide in a Brabender plastograf. The time of the torque maximum was proportional to the degree of crosslinking. The degree of crosslinking was determined by extraction and depended on the concentration of the crosslinking agent and of vinylacetate in the copolymer, and on the crosslinking temperature and time. It was found by DSC and by solid-state CP-MAS 13C NMR that with the progress of crosslinking the crystalline phase of the copolymers changed to the amorphous phase. Crosslinking took place mostly on the acetate groups. |
